Carotid revascularization rates vary widely across the USA
MedWire News: Use of carotid revascularization techniques vary widely among different US hospital referral regions, researchers report in the Archives of Internal Medicine.
Lesley Curtis (Duke Clinical Research Institute, Durham, North Carolina, USA) and team calculated age-standardized revascularization rates using data from almost 30 million Medicare beneficiaries, of whom over 300,000 underwent carotid endarterectomy (CEA) and more than 19,000 underwent carotid artery stenting (CAS).
CEA rates fell from 3.2 to 2.6 per 1000 beneficiaries between 2003 and 2006, while CAS rates rose slightly, from 0.3 per 1000 beneficiaries in 2005 (when codes for CAS first appeared in the Medicare database) to 0.4 per 1000 beneficiaries in 2006.
There was wide variation in CEA rates among hospital referral regions in the 2003-2004 period, from 0.79 per 1000 beneficiaries in Honolulu, Hawaii to 7.17 per 1000 beneficiaries in Beaumont, Texas - an almost nine-fold difference.
Variation was slightly less in the 2005-2006 period, ranging from 0.79 to 5.5 per 1000 beneficiaries for the same two regions, respectively.
Variation in CAS rates was less pronounced, yet the highest rate for 2005-2006, of 2.7 per 1000 beneficiaries in St Joseph, Michigan, was nearly eight times over the national average.
Among beneficiaries who underwent angiography from 2004 through 2006, the likelihood of undergoing revascularization was increased if they were male or had peripheral vascular disease. Patients were more likely to undergo CAS than no revascularization if they had coronary artery disease or had previously undergone CEA.
In an accompanying commentary, Ethan Halm (University of Texas Southwestern Medical Center, Dallas, USA) said that symptomatic disease is unlikely to vary so widely by region, so the "enthusiasm hypothesis" remains the most probable explanation for the findings.
This, he pointed out, may lead to an upswing in CAS use, a worrying possibility, as the current study shows that most revascularization patients in real-world practice are older than 70 years - an age group that reportedly does worse after CAS than CEA.
Halm said that recent conflicting trial results, combined with market pressure, are "expected to result in major pressure on Medicare to liberalize CAS coverage policy, despite the findings that surgery is preferred to stenting for revascularization in persons older than 70 years."
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By Eleanor McDermid